JP2009150701A - In-vehicle navigation apparatus and program for the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To compensate a functional constraint in a high-altitude area by supplying convenient route guiding information, on the basis of data read from a memory other than a hard disk, while travelling in the high-altitude area. <P>SOLUTION: A route computation processing section 29a calculates a route which reaches destination, and if the route passes through the high-altitude area, guidance data of a zone of the route passing through the high-altitude area are written in an external memory 24. A high-altitude area determining section 29b determines whether the route reaching the destination passes through the high-altitude area. A processing section 29c for determining the current position in the high-altitude area detects an event of passing through a diverging point on the route, while travelling the high-altitude area. A route guidance processing section 29d creates turn list data and writes them in the external memory 24. When the high-altitude area in the course of a route guidance is entered from the outside of the high-altitude area, a turn list is displayed, in place of the normal route guidance, based on the turn list data which has previously been stored in the external memory 24. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an in-vehicle navigation device having a hard disk drive, and more particularly, to access control to a hard disk drive in a high altitude area.

  Conventionally, map data and the like are stored in an in-vehicle device such as an in-vehicle navigation device that displays a map around the current position on the display based on the map data, or calculates an optimum route to the destination and provides driving guidance. As a storage medium, a hard disk drive is widely used. Also, using the large storage capacity of the hard disk drive, not only map data, but also application software for operating the in-vehicle navigation device and music for use with the audio function integrated in the in-vehicle navigation device Some data and video data are stored in a hard disk drive.

  A hard disk drive is a storage device that records or reads information using a magnetic head on a disk that is a storage medium coated with a magnetic material. When the hard disk drive is in operation, the magnetic head located above the disk is lifted from the disk by a slight amount by the pressure of air rotating with the disk rotating at high speed. Therefore, when the hard disk drive operates in an environment where the atmospheric pressure in the surrounding area is significantly reduced, the distance between the disk and the magnetic head cannot be maintained in an appropriate state due to a decrease in air pressure that causes the magnetic head to fly. As a result, there is a risk that the disk may be damaged by the collision between the disk and the magnetic head. Since the atmospheric pressure decreases as the altitude increases, the hard disk drive has a usage limit due to the altitude. Generally, the operation guarantee with respect to the altitude of the hard disk drive is up to an altitude of about 3000 m (about 0.7 atm) to 5000 m (about 0.5 atm).

  Therefore, in-vehicle devices equipped with hard disk drives are expected to be used in high altitudes (e.g., 3000m class or 4000-5000m class roads) that exceed the altitude where the operation of the hard disk drive is guaranteed. In this case, it is necessary to take measures to prevent the hard disk drive from being damaged.

Therefore, when the vehicle reaches a predetermined altitude (for example, 3000 m) or higher, a part of the map data stored in the hard disk drive is stored in the external memory, and then the hard disk drive is stopped and the high altitude of 3000 m or higher. A technique has been devised for performing route guidance based on map data stored in an external memory during traveling (see, for example, Patent Document 1). With this technology, it is possible to continue route guidance while preventing the hard disk drive from being damaged by stopping the hard disk drive at high altitudes.
JP 2004-317385 A

  However, as described in Patent Document 1, in order to store the map data in the range required during traveling in high altitudes in the external memory, a correspondingly large storage capacity is required. For this reason, providing a product with a storage medium having such a large storage capacity leads to an increase in product cost. Therefore, the function of saving the map data to the external memory at high altitude and continuing the route guidance even when the hard disk drive is stopped may not be implemented depending on the product as a result of considering the product cost and other circumstances. .

  In such a product, the function of the map data cannot be read by stopping the operation of the hard disk drive at a high altitude and the route guidance including the map display cannot be continued. As a result, in high altitudes, the convenience of the in-vehicle navigation device is remarkably lowered, and the user's trust in the product may be impaired. Therefore, it is possible to provide route guidance information even when traveling on high altitudes by a simple method that does not require a large-capacity storage medium, thereby limiting the functions caused by the hard disk drive not operating at high altitudes. It is important to compensate.

  The present invention has been made to solve the above-described problem. When driving in a high altitude, the data is read from an external memory or the like other than the hard disk drive instead of the route guidance that is performed by reading data from the hard disk drive as needed. The purpose is to provide a technique for compensating for functional restrictions in high altitudes by providing simple route guidance information based on data.

The vehicle-mounted navigation device according to claim 1 made to achieve the above object has the following characteristics.
A hard disk drive is provided as a storage means for storing map data. Based on the map data read from the hard disk drive, a route calculation to the destination and route guidance based on this are performed, and the current position of the vehicle is detected. A vehicle-mounted navigation device having a function of prohibiting the operation of the hard disk drive when it is determined that the current position detected by the position detection unit is a high altitude area including a region above a predetermined high altitude. In this case, determination area data storage means, list storage means, list generation means, high and high altitude determination means, and display control means are provided.

  The determination area data storage means includes a range that is a high altitude area and a range that is not a high altitude area with respect to the coordinate plane corresponding to the map coordinates indicated by the map data and the position coordinates detected by the position detection means. Stores high and high altitude judgment area data to be defined. The list generation means compares the route to the destination calculated in the route calculation with the high and high altitude determination area data stored in the determination area data storage means, and determines whether or not the route passes through the high and high altitude area. judge. If it is determined that the route passes through the high-altitude area, the branch points included in at least a section passing through the high-altitude area of the route and the guidance information regarding the route between the branch points are shown in the order of travel. Data for displaying the list is read from the map data stored in the hard disk drive, and stored in the list storage means as branch list data.

  The high and high altitude determination means compares the position coordinates detected by the position detection means with the high and high altitude determination area data stored in the determination area data storage means, thereby determining whether or not the current position is a high and high altitude area. Determine whether. In the course of route guidance based on the route to the destination calculated in the route calculation, the display control means performs a map from the hard disk drive while the current position is determined to be a high-altitude area by the high-altitude determination means. Instead of the route guidance performed by reading the data, a branch list based on the branch list data stored in the list storage means is displayed.

  The predetermined high altitude mentioned here is considered to be, for example, an altitude that reaches the upper limit value of altitude at which hard disk drive operation is guaranteed or the lower limit value of atmospheric pressure at which hard disk drive operation is guaranteed. It is done.

  According to the vehicle-mounted navigation device configured as described above, the branch stored in advance in the list storage means instead of the route guidance based on the map data read from the hard disk drive at any time while traveling in the high altitude area. By displaying the list, it is possible to compensate for the functional limitation when the hard disk drive operation is prohibited in the high altitude area.

  This branch list is a list of guidance information regarding the branch points on the route and the routes between the branch points. For example, the name of the branch point, the route between the branch points, the traveling direction at the branch point, the distance between the branch points, etc. A list of information is displayed in order of travel. The branch list having such a simple configuration has a much smaller data amount than the data necessary for route display using various guide images such as map display and intersection close-up images. Therefore, the storage capacity required for the list storage means for storing the branch list data is much smaller than when storing the map data in the range necessary for traveling in the high altitude area in the external memory. When implementing the function of the present invention, an increase in cost due to the addition of a storage device can be suppressed.

  Next, the in-vehicle navigation device according to claim 2 further includes an informing unit and a receiving unit, and inquires whether or not to display the branch list when entering the high altitude area from outside the high altitude area. A message to that effect is notified to the user via the notification means. As a response to this message, when an operation instruction for permitting display of the branch list is received through the receiving unit, a branch list based on the branch list data stored in the list storage unit is displayed. And

  With this configuration, it is possible to select whether or not to display the branch list according to the user's intention, which is convenient. In addition, it is necessary to switch from the normal route guidance to the branch list display by informing the message that the hard disk drive cannot be operated at high altitudes together with a message inquiring whether the branch list display is permitted or not. It is possible to make the user understand the circumstances that should not be.

  By the way, while the branch list is being displayed, the information regarding the branch points that have already passed and the route between the branch points is information that is less necessary for the user, and can be excluded from the display target. Also, if the number of branch lists that can be displayed on one screen is limited and all information in the branch list data cannot be displayed on one screen, the old information is excluded according to the progress of the vehicle, and instead it relates to the previous process. It is important to display new information.

  Therefore, the vehicle-mounted navigation device according to claim 3 may be configured. Specifically, the passage of the branch point included in the currently displayed branch list is determined based on the transition of the current position detected by the position detection unit, and the branch point that has passed and between the previous branch point and the branch point are determined. Information on the route is sequentially excluded from the display of the branch list, and branch information that has not been passed and is not displayed in the branch list data and information on the route between the branch points are sequentially added to the display of the branch list in the order of travel.

In order to determine the passage of the branch point, it may be determined, for example, based on whether or not the traveling locus of the vehicle based on the coordinates acquired by the position detecting means passes the coordinates of the branch point.
With this configuration, the contents of the currently displayed branch list are sequentially updated according to the progress of the vehicle, and the information on the process ahead of the current position is always displayed in the displayed branch list. . Therefore, it is easy for the user to grasp the progress status with respect to the process and information on the previous process, which is preferable.

  When determining the passage of a branch point, as described in claim 4, a range in which the current position is estimated to be included based on the current position detected by the position detection means and the accuracy with respect to the detection result. It is good to determine that it has passed the said branch point when the said branch point enters in this range. By doing in this way, even when there is an error in the detection result of the current position by the position detection means, it is possible to appropriately determine the passage of the branch point in a manner that takes into account the error.

  For example, when a GPS receiver is used as the position detection means, an accuracy degradation index (DPS) that is an index used for evaluating the positioning accuracy of GPS and a user equivalent ranging error (UERE) It is conceivable to use horizontal position accuracy (EPE: Estimated Position Error) obtained from The horizontal position accuracy EPE indicates a range in which the current position is estimated to exist in consideration of a positioning error by GPS. Therefore, it is considered that the reliability of the passage determination can be improved if it is determined that the branch point is within the EPE range centered on the coordinates of the current position and the branch point is passed. Moreover, when using a distance sensor, a gyro sensor, etc. other than a GPS receiver as a position detection means, you may comprise so that the error peculiar to each sensor may be added to the range estimated that the present position is included.

  By the way, when the branch point list data is generated based on the map data, a branch list relating to a branch point included in only a section passing through the high-altitude area among routes to the destination and a route between the branch points is generated. Instead, as described in claim 5, it may be configured to generate branch list data relating to branch points included in the entire process of the route to the destination and a route between the branch points.

  In this way, while traveling in the high altitude area, not only the guidance information in the high altitude area but also the guidance information regarding the further steps can be presented as a branch list, More information. Therefore, it is possible to sufficiently compensate for the functional limitation when the operation of the hard disk drive is prohibited in the high altitude area.

  In order to realize the list generation means, the high altitude determination means and the display control means in the in-vehicle navigation apparatus as described above in a computer system, the program is provided as a program that operates on the computer system as described in claim 6. Just do it. Such a program is recorded on a computer-readable storage medium such as a magnetic / optical / magneto-optical disk, a hard disk, a ROM, or a RAM, and loaded into the computer as necessary. Functions can be realized.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
[1. Description of configuration of in-vehicle navigation device 1]
FIG. 1 is a block diagram illustrating a schematic configuration of an in-vehicle navigation device 1 according to the embodiment.

  As shown in FIG. 1, the in-vehicle navigation device 1 includes a position detector 21 that detects the current position of the vehicle, an operation switch group 22 for inputting various instructions from a user, map data, a program, and the like. A hard disk drive (HDD) 23 that is a large capacity storage device, an external memory 24 that stores various information, a display device 25 for performing various displays such as a map display screen, and various guide voices are output. A voice output device 26 and a control unit 29.

  The position detector 21 receives a radio wave transmitted from an artificial satellite for GPS via a GPS antenna, detects a position coordinate of the vehicle, and a detection signal corresponding to the angular velocity of the rotational motion applied to the vehicle. Is provided, and a vehicle speed sensor 21c that outputs a detection signal corresponding to the speed of the vehicle is provided. Each of the sensors 21a to 21c has an error having a different property, and is configured to be used while complementing each other.

The operation switch group 22 includes a touch panel that is configured integrally with the display device 25 and installed on the display surface, and a mechanical key switch provided around the display device 25.
The hard disk drive 23 is a storage device in which a hard disk that stores information and a controller that includes a magnetic head, a drive unit, a control unit, and the like for reading and writing information to and from the hard disk are integrated. The hard disk drive 23 reads data from the hard disk based on the control from the control unit 29 and inputs the data to the control unit 29. Data stored in the hard disk drive 23 includes road data including node information and link information, map data including drawing data necessary for map display, so-called map matching data, route search / guidance data, These are various data including a program for operating the vehicle-mounted navigation device 1 and design image data. It is assumed that the hard disk drive 23 is guaranteed to operate normally in an environment where the altitude is 5000 m or less or 0.5 atmosphere or more.

  The external memory 24 stores various data such as high and high altitude determination area data, turn list data (corresponding to the branch list data of the present invention, details will be described later), and design image data for drawing the turn list. Is to do. As the external memory 24, a storage device (for example, a non-volatile semiconductor memory) that can rewrite the stored contents electrically or magnetically and can retain the stored contents even when the power is turned off is used.

  Here, the high and high altitude determination area data will be described with reference to FIG. FIG. 2 is an explanatory diagram schematically showing an overview of high-altitude determination area data. High and high altitude determination area data is data in which a code for identifying whether or not each area is a high and high altitude area is assigned to a mesh-like divided area obtained by dividing the map coordinate plane for each predetermined latitude and longitude. It is.

  For example, as shown in FIG. 2 (a), near the center of the map coordinate area having vertices of latitude / longitude coordinates (X1, Y1), (X2, Y1), (X1, Y2), (X2, Y2) , It is assumed that high altitude areas with an altitude of 5000 m or more are distributed in a patchy pattern. When creating high and high altitude determination area data corresponding to the map coordinate area, a divided area is defined by further dividing the map coordinate area. As shown in FIG. 2B, for a divided area including at least a part of a high altitude area with an altitude of 5000 m or more, a code “1” indicating that the divided area is a high altitude area. Assign. On the other hand, for a divided area that does not include a high altitude area with an altitude of 5000 m or higher, a code “0” indicating that the divided area is other than a high altitude area is assigned. The high and high altitude determination area data defined as described above is obtained for each divided area obtained by dividing the map coordinate area for a part or all of the map coordinate area indicated by the map data stored in the hard disk drive 23. Are stored in advance in the external memory 24 as table data for defining whether the area is a high-altitude area.

  Returning to the description of FIG. The display device 25 is a color display device having a display surface such as a liquid crystal display. The display device 25 can display various images on the display surface according to the input of the video signal from the control unit 29. For example, when the vehicle is traveling, the current position is indicated on a map around the current position identified from the current position of the vehicle detected by the position detector 21 and the map data input from the hard disk drive 23 as a navigation screen. Additional data such as a mark, a guide route to the destination, a name, a landmark, and various landmark symbols are displayed in an overlapping manner.

  The audio output device 26 is configured to notify the user of various types of information by voice. Thereby, various guidance such as route guidance can be given to the user both by the display by the display device 25 and the voice output from the voice output device 26.

  The control unit 29 is configured around a known microcomputer including a CPU, a ROM, a RAM, an I / O, a bus line connecting these configurations, and the like, and controls the above-described configuration of each unit. The control unit 29 executes various processes according to programs and various data read from the ROM, the hard disk drive 23, the external memory 24, and the like.

  For example, the navigation-related processing includes map display processing and route guidance processing. The map display process is a process of calculating the current position of the vehicle based on each detection signal from the position detector 21 and displaying a map or the like near the current position read from the hard disk drive 23 on the display device 25. The route guidance process is a destination that is the optimum route from the current position to the destination based on the point data stored in the hard disk drive 23 and the destination set in accordance with the operation of the operation switch group 22 or the like. This is a process for calculating a route and performing travel guidance to the destination in consideration of the relationship between the current position and the destination route. As a method for automatically setting an optimum route in this way, a method such as cost calculation by the Dijkstra method is known.

  The in-vehicle navigation device 1 is assumed to be used in an area that exceeds the upper limit of altitude (5000 m) at which normal operation of the hard disk drive 23 is guaranteed. Therefore, the control unit 29 prohibits the operation of the hard disk drive 23 and operates the hard disk drive 23 in an area of altitude 5000 m or more when entering a high altitude area including an area of altitude 5000 m or more while the vehicle is traveling. Prevent damage caused by.

  At this time, since the operation of the hard disk drive 23 is prohibited in the high altitude area, data necessary for map display and route guidance cannot be read from the hard disk drive 23 in the map display processing and route guidance processing described above. As a result, normal map display and route guidance cannot be continued while traveling in a highland area. Therefore, as a characteristic process of the present invention, the control unit 29, when traveling in the high altitude area, replaces the normal map display and route guidance, and branch points and branch points on the route to the destination. A turn list in which guide information related to the route between them is listed in order of travel is displayed on the display device 25.

  FIG. 3 is a functional block diagram schematically showing the correlation of various functions for displaying a turn list while traveling in a high altitude area. As shown in FIG. 3, the control unit 29 includes a route calculation processing unit 29 a, a high highland area determination processing unit 29 b, and a current position determination process in the highland area as functional blocks related to the display of the turn list in the highland area. A unit 29c, a route guidance processing unit 29d, and a drawing processing unit 29e.

  Among these, the route calculation processing unit 29a calculates a route to the destination inputted by the user, and when this route passes through the high-altitude area, a branch point and a route in a section passing through the high-high-area area. Is written in the external memory 24 ("route calculation process"). The high-altitude area determination processing unit 29b compares the route calculated by the route calculation processing unit 29a with the high-highland determination area data, and determines whether the route passes through the high-highland area.

The high-altitude area current position determination processing unit 29c determines the current position from the detection result of the position detector 21 while traveling in the high-high area, and detects passage of a branch point.
The route guidance processing unit 29d executes “route guidance processing”, “route guidance switching processing”, and “turn list display processing”. In the “route guidance process”, turn list data is generated depending on whether the route to the destination passes through the high altitude area and is written in the external memory 24 or is usually generated without generating the turn list data. The route guidance is started. In the “route guidance switching process”, when the route guidance is entered from the high altitude area to the high altitude area, the normal map display and the route guidance are switched to the turn list display. In the “turn list display process”, the turn list is displayed based on the turn list data recorded in advance in the external memory 24.

  The drawing processing unit 29e displays a map, a guide image, and the like based on the map data and design image data read from the hard disk drive 23 in a normal time while traveling outside the high altitude area, and displays the inside of the high altitude area. During traveling, turn list display based on turn list data and design image data read from the external memory 24 is performed.

The detailed contents of the series of processes described above will be described later.
The schematic configuration of the in-vehicle navigation device 1 has been described above, but the correspondence between the configuration of the in-vehicle navigation device 1 in the present embodiment and the configuration described in the claims is as follows. The position detector 21 of the vehicle-mounted navigation device 1 according to the present embodiment corresponds to the position detection means in the claims. The external memory 24 corresponds to determination area data storage means and list storage means. Further, the display device 25 corresponds to a notification unit. Further, the operation switch group 22 corresponds to a receiving unit. The control unit 29 corresponds to a list generation unit, a high and high altitude determination unit, and a display control unit.

[2. Description of each process executed by control unit 29]
Hereinafter, detailed contents of various processes executed by the control unit 29 will be described based on the flowcharts of FIGS. 4 to 8 and 10 and the explanatory diagrams of FIGS.

[2-1. Explanation of overall processing]
FIG. 4 is a flowchart showing the procedure of the entire route guidance process executed by the control unit 29. This whole process is started when the power of the vehicle-mounted navigation device 1 is turned on.

  First, the control unit 29 detects the current position of the vehicle based on the input signal from the position detector 21 (S10). Next, map data around the current position is read from the hard disk drive 23 (S20). Based on the read map data, a screen in which a mark indicating the current position and a map around the current position are overlapped is displayed on the display device 25 (S30).

  After displaying the map around the current position, it is determined whether or not the destination is set by performing a predetermined operation from the user (S40). If the destination is not set (S40: NO), the process returns to S10. On the other hand, when it is determined that the destination has been set (S40: YES), a “route calculation process” for calculating a route from the current position to the destination is executed (S50). The detailed contents of the “route calculation process” will be described later. After executing the “route calculation process”, the route guidance is performed according to the route to the destination, and the “route guidance process” for displaying the turn list in the high altitude area is executed (S60). The detailed contents of the “route guidance process” will be described later.

[2-2. Explanation of “Route calculation process”
FIG. 5 is a flowchart illustrating a procedure of “route calculation processing” executed by the control unit 29. This process is a process executed in S50 of the above-described overall process (see FIG. 4).

  The control unit 29 first acquires map data around the set destination from the hard disk drive 23 (S51). And it is determined whether the instruction | indication from the user for starting a route calculation was input (S52). Here, this process is repeated while the instruction from the user is not input (S52: NO). And when it determines with the instruction | indication from the user for starting a route calculation having been input (S52: YES), based on the point data contained in map data and the set destination, from a present position to the destination The optimum route is calculated (S53).

  Subsequently, the calculated route to the destination and the high altitude determination area data stored in the external memory 24 are compared to determine whether the route to the destination passes through the high altitude area. High altitude area determination processing is performed (S54). As a result of the high-altitude area determination process, when it is determined that the route to the destination does not pass through the high-altitude area (S55: NO), the “route calculation process” is terminated.

  On the other hand, if it is determined that the route to the destination passes through the high highland area as a result of the high highland area determination processing (S55: YES), this indicates that the route to the destination passes through the high highland area. The high-altitude area flag, which is identification information, is set on (S56). Then, the guide data regarding the branch points included in the section passing through the high-altitude area in the route to the destination and the route between the branch points are acquired from the map data in the hard disk drive 23 and written in the external memory 24. (S57). The guidance data acquired from the map data includes, for example, data indicating the position coordinates of the branch points, the names of the branch points and the paths between the branch points, the distance between the branch points, and the like.

[2-3. Explanation of “route guidance processing”
FIG. 6 is a flowchart showing a procedure of “route guidance processing” executed by the control unit 29. This process is a process executed in S60 of the overall process described above (see FIG. 4).

  First, the control unit 29 determines whether or not the high-altitude area flag is on (S61). Here, when it is determined in S61 that the high-altitude area flag is ON (S61: YES), each starting point and branch point are based on the route to the destination and the guidance data stored in the external memory 24. Turn list data for displaying a turn list showing the guidance information of the route between them in order of travel is created (S62). In this turn list data, in addition to the guidance data regarding the branch point and the route between the branch points already acquired from the hard disk drive 23, information such as the direction of travel at the branch point and the route from the start point to the destination is included. It is added based on the route to the ground.

  After the turn list data is created, the created turn list data is written in the external memory 24 (S63), and the “route guidance switching process” is started (S64). In this “route guidance switching process”, normal route guidance is performed using a map display or guide voice along the route to the destination while traveling outside the high altitude area. On the other hand, when entering the high-altitude area, the normal route guidance is switched to the turn list display, and the turn list is displayed until the vehicle leaves the high-altitude area or arrives at the destination. The detailed contents of the “route guidance switching process” will be described later.

  On the other hand, when it is determined in S61 that the high-altitude area flag is off (S61: NO), normal route guidance (hereinafter referred to as “normal guidance”) that provides travel guidance by map display or guide voice along the route to the destination. (Also referred to as “process”) is started (S65). In the “normal guidance process”, map data, design image data, and the like necessary for route guidance are read from the hard disk drive 23 as needed, and the process is executed. Since this “normal guidance processing” is the same as the conventional route guidance, detailed description thereof is omitted here.

[2-4-1. Explanation of “Route Guidance Switching Process (First Embodiment)”
FIG. 7 is a flowchart showing the procedure of the “route guidance switching process” executed by the control unit 29 in the first embodiment. This process is a process executed in S64 of the above-mentioned “route guidance process” (see FIG. 6).

  First, the control unit 29 detects the current position of the vehicle based on the input signal from the position detector 21 and compares this with the high and high altitude determination area data to determine whether the current position corresponds to the high and high altitude area. It is determined whether or not (S611). If it is determined that the current position does not correspond to the high-altitude area (S611: NO), the route guidance is executed in the above-described “normal guidance process” (S612), and the process returns to S611.

  On the other hand, if it is determined in S611 that the current position corresponds to the high-altitude area (S611: YES), the route guidance by the above-mentioned “normal guidance processing” is stopped and the turn list data stored in the external memory 24 is controlled. Data is read out to the working memory in the unit 29 (S613). Then, based on the data stored in the external memory 24, switching to execution of “turn list display processing” for displaying the turn list on the display device 25 (S614). Details of the “turn list display process” will be described later. When it is determined that the vehicle has entered the high altitude area, the operation of the hard disk drive 23 is prohibited.

  After performing the “turn list display process”, it is determined whether the vehicle has reached the destination based on the input signal from the position detector 21 (S615). If it is determined that the vehicle has not reached the destination (S615: NO), the process returns to S611. On the other hand, if it is determined that the vehicle has reached the destination (S615: YES), the “route guidance switching process (first embodiment)” is terminated.

[2-4-2. Description of “Route Guidance Switching Process (Second Embodiment)”
FIG. 8 is a flowchart illustrating a procedure of the “route guidance switching process” executed by the control unit 29 according to the second embodiment. This process is a process executed in S64 of the above-mentioned “route guidance process” (see FIG. 6).

  First, the control unit 29 detects the current position of the vehicle based on the input signal from the position detector 21 and compares this with the high and high altitude determination area data to determine whether the current position corresponds to the high and high altitude area. It is determined whether or not (S621). If it is determined that the current position does not correspond to the high altitude area (S621: NO), the route guidance is executed in the above-described “normal guidance process” (S622), and the process returns to S621.

  On the other hand, if it is determined in S621 that the current position corresponds to a high-altitude area (S621: YES), the route guidance by the above-mentioned “normal guidance processing” is stopped, and the user is inquired about whether or not to display the turn list. (See FIG. 9) is displayed on the display device 25 (S623). When it is determined that the vehicle has entered the high altitude area, the operation of the hard disk drive 23 is prohibited.

  Here, specific contents of the message displayed in S623 will be described with reference to FIG. FIG. 9 is an explanatory diagram illustrating an example of a message display for inquiring permission / inhibition of the turn list display.

  As shown in FIG. 9, a message is displayed on the screen notifying that the operation of the hard disk drive 23 is stopped in the high altitude area and the map cannot be displayed, and prompting an operation for switching to the turn list display. It is displayed. In addition, a button 251 for starting turn list display is displayed as an icon configured with a GUI, and when the user presses this button 251, an instruction for starting display of the turn list is input. Can do.

  Returning to the flowchart of FIG. After displaying a message asking whether to permit the display of the turn list in S623, the system waits for an instruction to permit the display of the turn list (S624). If it is determined that an instruction to permit display of the turn list has been input (S624: YES), the turn list data stored in the external memory 24 is read to the work memory in the control unit 29 (S625). . Then, “turn list display processing” for displaying the turn list on the display device 25 based on the data stored in the external memory 24 is executed (S626). Details of the “turn list display process” will be described later.

  After performing the “turn list display process”, it is determined whether or not the vehicle has reached the destination based on the input signal from the position detector 21 (S627). If it is determined that the vehicle has not reached the destination (S627: NO), the process returns to S621. On the other hand, if it is determined that the vehicle has reached the destination (S627: YES), the “route guidance switching process (second embodiment)” is terminated.

[2-5. Explanation of “Turn list display process”
FIG. 10 is a flowchart showing the procedure of “turn list display processing” executed by the control unit 29. This process is a process executed in S614 and S626 of the above-described “route guidance switching process (first and second embodiments)” (see FIGS. 7 and 8).

  First, the control unit 29 sets data of a branch point to be passed next from the turn list data held in the work memory (S701). Based on the data related to the route in the turn list data, the distance from the current position to the next branch point is calculated and set (S702). Subsequently, based on the data set in S701 and S702, the turn list data held in the work memory, the design image data stored in the external memory 24, and the like, the turn list starting from the current position is displayed on the display device 25. (S703).

Here, the specific contents of the turn list displayed in S703 will be described with reference to FIG. FIG. 11 is an explanatory diagram showing an example of the display of the turn list.
As shown in FIG. 11, in the turn list, a mark 252b indicating the current position and a mark 252a indicating the name “CURRENT ROAD” of the road that is currently running are displayed at the bottom of the screen. Various marks indicating branching points and the like from the starting point to the upper part of the screen are displayed as a list in the order of travel. Here, the arrow marks 253b, 254b, and 255b are marks for guiding the traveling directions at the branch points, respectively. Further, marks 253a, 254a, and 255a that are displayed so as to overlap each arrow mark are marks that indicate the names of the roads that have advanced in the direction indicated by the arrow mark at the branch point.

  The indicator 256a indicates the distance along the route from the current position to the next branch point, and the indicators 256b and 256c are indicators that indicate the distance between the branch points along the route, respectively.

  In the turn list shown in FIG. 11, only the list from the current position to the third branch point is displayed, but the entire list can be displayed by pressing the “▲” icon 257a composed of GUI. It is possible to scroll downward and to display information on the further branch points in the order of travel. In order to return the list scrolled to the bottom of the screen, the entire list can be scrolled to the top of the screen by pressing the “▼” icon 257b. However, it does not return to the list of branch points or routes before the current position.

In addition, a gauge 258 indicating the degree of progress of the current position with respect to the entire route to the destination is displayed at the left end of the screen.
Returning to the flowchart of FIG. After starting the display of the turn list in S703, it is determined whether or not the current position has moved since the previous determination (S704). Here, while it is determined that the current position has not moved (S704: NO), this process is repeated. If it is determined that the current position has moved (S704: YES), it is determined whether the current position has reached either the destination or escape from the high altitude area (S705). The determination of arrival at the destination is made by comparing the coordinates of the destination with the coordinates of the current position, and when escaping from the high-altitude area, the coordinates of the current position are checked against the high-altitude determination area data To do.

  In S705, when it is determined that neither the arrival at the destination nor the escape from the high-altitude area is applicable (S705: NO), it is determined whether or not the next branch point has been passed (S706). Note that the passage of the branch point is performed by comparing the coordinates of the branch point with the current position. At this time, in order to more reliably determine the passage of the branch point, the passage is determined in consideration of the positioning error by the position detector 21. Specifically, the horizontal position accuracy EPE is calculated from the accuracy degradation index DOP and the user equivalent distance measurement error UERE in the GPS receiver 21a, and the coordinates of the branch point are within the range of the EPE centered on the coordinates of the current position. By entering, it is determined that the branch point has been passed. The EPE indicates a range in which the current position is expected to exist in consideration of a positioning error by GPS. Therefore, the reliability of the passage determination can be improved by determining that the branch point has passed since the coordinates of the next branch point are within the EPE range.

  If it is determined in S706 that the next branch point has not been passed (S706: NO), the process proceeds to S702, and the distance from the current position to the next branch point is recalculated. Based on this calculation result, a turn list in which the contents of the indicator 256a (see FIG. 11) indicating the distance to the next branch point and the gauge 258 (see FIG. 11) indicating the degree of progress with respect to the entire route is updated. It is displayed (S703).

  On the other hand, when it is determined in S706 that the next branch point has been passed (S706: YES), the process proceeds to S701, and the data of the branch point to be passed next is reset. Subsequently, the distance from the current position to the next branch point is calculated, and this is reset (S702). Then, based on the reset data, information on the branch points and routes that have already been passed is excluded from the displayed turn list, and the information on each branch point travels upward from the screen starting from the name of the road that is currently running. The display contents of the turn list are updated by arranging them in order (S703). In addition, the contents of gauges indicating the degree of progress with respect to the travel of the entire route and the indicators indicating the distance between the next branch points are updated as appropriate.

  As described above, the display of the turn list is sequentially updated according to the progress of the vehicle by sequentially repeating the processes of S701 to S706. If it is determined in S705 that the destination is reached or the vehicle exits from the high altitude area (S705: YES), the “turn list display process” is terminated.

[3. effect]
According to the in-vehicle navigation device 1 of the present embodiment, the following effects can be obtained.
(1) While driving in a high altitude area, instead of route guidance that is performed by reading data from the hard disk drive 23 at any time, a turn list stored in advance in the external memory 24 is displayed. It is possible to compensate for the functional limitation when the operation of the hard disk drive 23 is prohibited in the area.

  (2) The storage capacity required to store the turn list data is much smaller than when storing the map data in the range required during traveling in the high altitude area in the external memory 24. When implementing the functions of this embodiment, it is possible to suppress an increase in cost due to the increase in the storage capacity of the external memory 24.

  (3) In the “route guidance switching process” (see FIG. 8) of the second embodiment, a message (see FIG. 9) for inquiring whether to permit the display of the turn list is displayed. This is convenient because it is possible to select whether or not there is a user's intention. Furthermore, by displaying a message explaining that the hard disk drive 23 cannot be operated at high altitudes along with a message inquiring whether the turn list display is permitted or not, it is possible to switch from the normal route guidance to the turn list display. It is possible to make the user understand the circumstances that must be done.

  (4) By sequentially updating the contents of the displayed turn list in accordance with the progress of the vehicle, information on the process ahead of the current position is always displayed in the displayed turn list. Therefore, it is preferable that the user can easily grasp the progress status with respect to the process and information on the previous process.

[4. Another embodiment]
As mentioned above, although embodiment of this invention was described, this invention can be implemented in various aspects.

  For example, in the above embodiment, when obtaining the guidance data for generating the turn list data in S57 of the “route calculation process” (see FIG. 5), the route passes through the high altitude area among all the routes to the destination. Only the branch point included in the section to be and the route guidance data between the branch points are acquired. On the other hand, the configuration may be such that not only the section passing through the high altitude area, but also the branch points of all sections of the route and the guidance data between the branch points are read. In this way, while traveling in a high-altitude area, not only the guidance information in the high-altitude area, but also guidance information regarding the process ahead can be presented as a turn list. More information.

  In the above embodiment, the determination is made based on the high and high altitude determination area data stored in the external memory 24 when determining whether or not the current position corresponds to the high high area. The method for determining the altitude of the current position is not limited to this. For example, the altitude may be measured by three-dimensional positioning based on a radio signal from a satellite received by the GPS receiver 21a, and it may be determined whether or not it corresponds to a high altitude area based on the measured altitude. Further, the altitude may be specified by the atmospheric pressure measured by the atmospheric pressure sensor.

It is a block diagram showing a schematic structure of in-vehicle navigation device 1 of an embodiment. It is explanatory drawing which shows the outline | summary of high-altitude determination area data typically. It is a functional block diagram which shows typically the correlation of the various functions for displaying a turn list. It is a flowchart which shows the procedure of the whole process of route guidance. It is a flowchart which shows the procedure of a "route calculation process." It is a flowchart which shows the procedure of "route guidance processing". It is a flowchart which shows the procedure of 1st Embodiment of a "route guidance switching process." It is a flowchart which shows the procedure of 2nd Embodiment of "route guidance switching processing." It is explanatory drawing which shows an example of the display of the message which inquires the permission of the display of a turn list. It is a flowchart which shows the procedure of a "turn list display process." It is explanatory drawing which shows an example of the display of a turn list.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Vehicle-mounted navigation apparatus, 21 ... Position detector, 21a ... GPS receiver, 21b ... Gyroscope, 21c ... Vehicle speed sensor, 22 ... Operation switch group, 23 ... Hard disk drive, 24 ... External memory, 25 ... Display apparatus, 26 ... Audio output device, 29 ... Control unit

Claims (6)

A hard disk drive is provided as a storage means for storing map data. Based on the map data read from the hard disk drive, a route calculation to the destination and route guidance based on this are performed, and the current position of the vehicle is detected. In-vehicle navigation having a function of prohibiting the operation of the hard disk drive when it is determined that the current position detected by the position detection means is a high altitude area including an area above a predetermined high altitude. A device,
A height that defines a range that is the high altitude area and a range that is not the high altitude area with respect to the coordinate plane corresponding to the map coordinates indicated by the map data and the position coordinates detected by the position detecting means. Determination area data storage means for storing high altitude determination area data;
List storage means for storing branch list data;
When the route to the destination calculated in the route calculation is compared with the high and high altitude determination area data stored in the determination area data storage means, and when it is determined that the route passes through the high and high altitude area, A map in which data for displaying a branch list indicating the branching information included in a section passing through at least the high altitude area of the route and guidance information regarding the route between the branch points in the order of travel is stored in the hard disk drive List generation means for reading out data and storing it in the list storage means as branch list data;
By comparing the position coordinates detected by the position detecting means with the high and high altitude determination area data stored in the determination area data storage means, it is determined whether or not the current position is the high and high altitude area. High altitude judging means;
In the course of route guidance based on the route to the destination calculated in the route calculation, the map data from the hard disk drive is determined while the current position is determined to be the high and high altitude area by the high and high altitude determining means. A vehicle-mounted navigation device comprising: display control means for displaying a branch list based on the branch list data stored in the list storage means instead of the route guidance performed by reading out the route information. The in-vehicle navigation device according to claim 1,
An informing means for informing the user of information;
Receiving means for receiving an operation instruction from the user,
When the display control means enters the high high altitude area from outside the high altitude area, the display control means notifies the user via the notification means of a message to inquire whether or not to display the branch list. As a response to this message, when an operation instruction for permitting display of the branch list is accepted through the accepting means, a branch list based on the branch list data stored in the list storage means is displayed. A vehicle-mounted navigation device. In the in-vehicle navigation device according to claim 1 or 2,
The display control means determines the passage of the branch point included in the currently displayed branch list based on the transition of the current position detected by the position detection means, the branch point that has passed, and the previous branch point and branch point. Information on the route between them is sequentially excluded from the display of the branch list, and branch information that has not been passed and is not displayed in the branch list data and information on the route between the branch points is displayed in the order of travel. In-vehicle navigation device characterized by being added to The in-vehicle navigation device according to claim 3,
The display control means specifies a range where the current position is estimated to be included based on the current position detected by the position detection means and the accuracy with respect to the detection result, and the branch point falls within this range. Therefore, it is determined that the vehicle has passed the branch point. The in-vehicle navigation device according to any one of claims 1 to 4,
When the list generation means determines that the route to the destination calculated in the route calculation passes through the high altitude area, the branch point included in the entire process of the route and the branch relating to the route between the branch points A vehicle-mounted navigation device, wherein list data is read from map data stored in the hard disk drive and stored in the list storage means.   A program for controlling a computer used in the in-vehicle navigation device according to any one of claims 1 to 5, wherein the computer generates the list generation unit, the high and high altitude determination unit, and the display. A program for functioning as a control means.